Nefopam is a centrally-acting non-opioid analgesic drug of the benzoxazocine chemical class. Nefopam has been known since the 1960s and its synthesis is described in U.S. Pat. No. 3,830,803. Nefopam is currently available around the world, but has not been approved by the U.S. Food and Drug Administration.
N-desmethyl nefopam is one metabolite of nefopam and is believed to exhibit biological activity.
Moderate to severe pain is often treated using opioids, which are a class of drugs known to have strong analgesic effects in humans. However, opioids have numerous undesirable side effects such as itchiness, sedation, nausea, respiratory depression, constipation, and euphoria. Furthermore, continuous opioid use can lead to dependence often resulting in withdrawal syndrome. Moreover, because of the euphoric effects of opioids, recreational use is common and may lead to accidental overdose and death from respiratory depression. Currently, the United States is experiencing an increase in the rates of recreational use of opioids and addiction, which many attribute to the over-prescription of opioids for pain management.
Accordingly, there is a need for an alternative to opioids in the treatment of pain that is effective as an analgesic but produces fewer side effects, does not produce respiratory depression, and has less abuse potential than opioids. Similarly, there is also a need for effective treatments of pain that allow for reduced doses of opioids to thereby reduce the incidences of side effects and dependency.